The present invention relates to a texture spraying apparatus for discharging a texture material onto a surface, and more particularly to an aerosol spray texture apparatus particularly adapted to discharge a texture material having particulate matter contained therein.
Buildings are commonly comprised of a frame to which a roof, exterior walls, and interior walls and ceilings are attached. The interior walls and ceilings are commonly formed using sheets of drywall material that are attached to frame, usually by screws. Gaps are normally formed between adjacent sheets of drywall material. In addition, the screws are countersunk slightly, and the screw heads are visible.
To hide the gaps and screw heads, they are covered with tape and/or drywall compound and sanded so that the interior surfaces (wall and ceiling) are smooth and continuous. The interior surfaces are then primed for further finishing.
After the priming step, a texture material is often applied to interior surfaces before painting. The texture material forms a bumpy, irregular surface that is aesthetically pleasing. The textured interior surface also helps to hide irregularities in the interior surface.
Some interior surfaces, especially ceilings, are covered with a special type of texture material referred to as acoustic texture material. Acoustic texture material contains particulate material that adheres to the interior surface. The purpose of the particulate material is partly aesthetic and partly functional. The particles absorbs rather than reflects sound and thus can reduce echo in a room. The term xe2x80x9cacousticxe2x80x9d texture material is used because of the sound absorptive property of this type of texture material.
When repairs are made to interior walls and ceilings, the texture material often must be reapplied. The newly applied texture material should match the original texture material.
A number of products are available that allow the application of texture material in small quantities for the purpose of matching existing texture material. In addition to hopper based dispensing systems, texture material may be applied in small quantities using aerosol systems. With conventional texture material that does not include particles, a variety of oil and water based texture materials in aerosol dispensing systems are available.
Acoustic texture materials pose problems that have heretofore limited the acceptance of aerosol dispensing systems. In particular, most acoustic texture materials contain polystyrene chips that dissolve in commercially available aerosol propellant materials. Thus, conventional aerosol propellant materials are not available for use with acoustic texture materials.
The Applicants have sold since approximately 1995 a product that employs compressed inert gas, such as air or nitrogen, as the propellant. The compressed gas does not interact with the particles in the acoustic texture material. The compressed air resides in the upper portion of the aerosol container and forces the acoustic texture material out of the container through a dip tube that extends to the bottom of the container.
While commercially viable, the use of compressed inert gas to dispense acoustic texture material from an aerosol container assembly presents several problems. First, if the aerosol system is operated while inverted, the compressed inert gas escapes and the system becomes inoperative. Second, the compressed inert gas can force all of the acoustic texture material out of the aerosol container in a matter of seconds. An inexperienced user can thus inadvertently and ineffectively empty the entire container of acoustic texture material.
The Applicants are also aware of an aerosol product that sprays a foam material instead of a true acoustic texture material. The foam material does not contain particulate material, and thus the resulting texture formed does not match an existing coat of true acoustic texture material.
The need thus exists for a system for dispensing acoustic texture material that provides the convenience of an aerosol dispensing system, employs true acoustic texture material, and is easily used by inexperienced users.
There are in the prior art various devices to spray a texture material onto a wall surface or a ceiling. Depending upon the nature of the composition and other factors, the material that is sprayed onto the surface as a coating can have varying degrees of xe2x80x9croughnessxe2x80x9d.
In some instances, the somewhat roughened texture is achieved by utilizing a textured composition that forms into droplets when it is dispensed, with the material then hardening with these droplets providing the textured surface. In other instances, solid particulate material is mixed with the liquid texture material so that with the particulate material being deposited with the hardenable liquid material on the wall surface, these particles provide the textured surface. However, such prior art aerosol spray texture devices have not been properly adapted to deliver a texture having particulate matter therein to provide the rougher texture.
In particular, the Applicants are aware of prior art spray texture devices using an aerosol container which contains the texture material mixed with a propellant under pressure and from which the textured material is discharged onto a surface. Such aerosol dispensers are commonly used when there is a relatively small surface area to be covered with the spray texture material. Two such spray texture devices are disclosed in U.S. Pat. No. 5,037,011, issued Aug. 6, 1991, and more recently U.S. Pat. No. 5,188,263, issued Feb. 23, 1993 with John R. Woods being named inventor of both of these patents.
Additionally, the Assignee of the present invention has since approximately 1983 manufactured and sold manually operated devices for applying spray texture material onto walls and ceilings. These spray texture devices are described in one or more of the following U.S. Pat. Nos.: 4,411,387; 4,955,545; 5,069,390; 5,188,295.
Basically, these spray texture devices comprised a hopper containing hardenable material, a manually operated pump, and a nozzle. By pointing the device at the area being patched and operating the manual pump, the hardenable material and pressurized air generated by the pump were mixed in the nozzle and subsequently sprayed onto the area being patched.
When applied to a ceiling, the hardenable material employed by these prior art spray texture devices basically comprised a mixture of the following ingredients:
a. water to form a base substance and a carrier for the remaining ingredients;
b. a filler substance comprising clay, mica, and/or calcium carbonate;
c. an adhesive binder comprising natural and/or synthetic polymers; and
d. an aggregate comprising polystyrene particles.
The filler, adhesive binder, and aggregate are commercially available from Hamilton Materials, Inc. under the tradename PurTex.
The hardenable material employed by these prior art spray texture devices further comprised one or more of the following additional ingredients, depending upon the circumstances: thickeners, surfactants, defoamers, antimicrobial materials, and pigments.
The present invention is a dispensing system that allows a predetermined, metered quantity of material to be dispensed from an aerosol container. The dispensing system is particularly adapted to dispense acoustic texture material including particles of polystyrene mixed throughout.
The present invention comprises a container system for containing the texture material and a compressed inert gas as a propellant, a valve assembly operable in an open and close configuration for allowing or preventing fluid flow from the container assembly, an outlet assembly for dispersing the texture material dispensed thereby, and a metering assembly that interacts either with the valve assembly or the outlet assembly to allow the user to control the amount of texture material dispensed.
The metering system may be as simple as a collar that limits the outlet assembly to limit the flow rate of the texture material exiting the system and thus provide the user with more control over the amount of texture material dispensed.
A more complex system requires the user to depress an actuator member fully at which point the metering assembly will release the valve assembly and cause the valve assembly to return to its closed position without any interaction by the user.
An even more complex system may require the user to press an actuator member to energize the system. After the actuator member has been depressed by a predetermined amount, the valve is triggered open and then released to close without further input from the user. In this case, the user has no control over the amount of texture material dispensed and thus cannot inadvertently dispense the entire contents of the can.
The metering assembly can be mounted within the container assembly or above the container assembly around the valve stem. Another type of metering assembly is located completely outside of the container and simply acts on a conventional valve assembly.